Rotation code is the easy half; the abuse half is that sticky and rotating residential exits both land on consumer ASNs. A session that looked clean an hour ago can be a busy shared exit after the pool recycles.

If the path is used for anything account-sensitive (not just scraping), checking the current egress for fresh proxy-class evidence before auth is cheap hygiene. IP99 (ThreatHunter) exposes usage_type, proxy/VPN signals, and evidence age on a free no-key lookup—soft mention only, not a substitute for site rules.